openstack-manuals/doc/config-reference/source/block-storage/drivers/zfssa-iscsi-driver.rst

Oracle ZFS Storage Appliance iSCSI driver

Oracle ZFS Storage Appliances (ZFSSAs) provide advanced software to protect data, speed tuning and troubleshooting, and deliver high performance and high availability. Through the Oracle ZFSSA iSCSI Driver, OpenStack Block Storage can use an Oracle ZFSSA as a block storage resource. The driver enables you to create iSCSI volumes that an OpenStack Block Storage server can allocate to any virtual machine running on a compute host.

Requirements

The Oracle ZFSSA iSCSI Driver, version 1.0.0 and later, supports ZFSSA software release 2013.1.2.0 and later.

Supported operations

• Create, delete, attach, detach, manage, and unmanage volumes.
• Create and delete snapshots.
• Create volume from snapshot.
• Extend a volume.
• Attach and detach volumes.
• Get volume stats.
• Clone volumes.
• Migrate a volume.
• Local cache of a bootable volume.

Configuration

1. Enable RESTful service on the ZFSSA Storage Appliance.

2. Create a new user on the appliance with the following authorizations:

   scope=stmf - allow_configure=true
   scope=nas - allow_clone=true, allow_createProject=true, allow_createShare=true, allow_changeSpaceProps=true, allow_changeGeneralProps=true, allow_destroy=true, allow_rollback=true, allow_takeSnap=true

   You can create a role with authorizations as follows:

   zfssa:> configuration roles
   zfssa:configuration roles> role OpenStackRole
   zfssa:configuration roles OpenStackRole (uncommitted)> set description="OpenStack Cinder Driver"
   zfssa:configuration roles OpenStackRole (uncommitted)> commit
   zfssa:configuration roles> select OpenStackRole
   zfssa:configuration roles OpenStackRole> authorizations create
   zfssa:configuration roles OpenStackRole auth (uncommitted)> set scope=stmf
   zfssa:configuration roles OpenStackRole auth (uncommitted)> set allow_configure=true
   zfssa:configuration roles OpenStackRole auth (uncommitted)> commit

   You can create a user with a specific role as follows:

   zfssa:> configuration users
   zfssa:configuration users> user cinder
   zfssa:configuration users cinder (uncommitted)> set fullname="OpenStack Cinder Driver"
   zfssa:configuration users cinder (uncommitted)> set initial_password=12345
   zfssa:configuration users cinder (uncommitted)> commit
   zfssa:configuration users> select cinder set roles=OpenStackRole

   Note

   You can also run this workflow to automate the above tasks.

3. Ensure that the ZFSSA iSCSI service is online. If the ZFSSA iSCSI service is not online, enable the service by using the BUI, CLI or REST API in the appliance.

   zfssa:> configuration services iscsi
   zfssa:configuration services iscsi> enable
   zfssa:configuration services iscsi> show
   Properties:
   <status>= online
   ...

   Define the following required properties in the cinder.conf file:

   volume_driver = cinder.volume.drivers.zfssa.zfssaiscsi.ZFSSAISCSIDriver
   san_ip = myhost
   san_login = username
   san_password = password
   zfssa_pool = mypool
   zfssa_project = myproject
   zfssa_initiator_group = default
   zfssa_target_portal = w.x.y.z:3260
   zfssa_target_interfaces = e1000g0

   Optionally, you can define additional properties.

   Target interfaces can be seen as follows in the CLI:

   zfssa:> configuration net interfaces
   zfssa:configuration net interfaces> show
   Interfaces:
   INTERFACE STATE CLASS LINKS    ADDRS          LABEL
   e1000g0   up    ip    e1000g0  1.10.20.30/24  Untitled Interface
   ...

   Note

   Do not use management interfaces for zfssa_target_interfaces.

ZFSSA assisted volume migration

The ZFSSA iSCSI driver supports storage assisted volume migration starting in the Liberty release. This feature uses remote replication feature on the ZFSSA. Volumes can be migrated between two backends configured not only to the same ZFSSA but also between two separate ZFSSAs altogether.

The following conditions must be met in order to use ZFSSA assisted volume migration:

• Both the source and target backends are configured to ZFSSAs.
• Remote replication service on the source and target appliance is enabled.
• The ZFSSA to which the target backend is configured should be configured as a target in the remote replication service of the ZFSSA configured to the source backend. The remote replication target needs to be configured even when the source and the destination for volume migration are the same ZFSSA. Define zfssa_replication_ip in the cinder.conf file of the source backend as the IP address used to register the target ZFSSA in the remote replication service of the source ZFSSA.
• The name of the iSCSI target group(zfssa_target_group) on the source and the destination ZFSSA is the same.
• The volume is not attached and is in available state.

If any of the above conditions are not met, the driver will proceed with generic volume migration.

The ZFSSA user on the source and target appliances will need to have additional role authorizations for assisted volume migration to work. In scope nas, set allow_rrtarget and allow_rrsource to true.

zfssa:configuration roles OpenStackRole auth (uncommitted)> set scope=nas
zfssa:configuration roles OpenStackRole auth (uncommitted)> set allow_rrtarget=true
zfssa:configuration roles OpenStackRole auth (uncommitted)> set allow_rrsource=true

ZFSSA local cache

The local cache feature enables ZFSSA drivers to serve the usage of bootable volumes significantly better. With the feature, the first bootable volume created from an image is cached, so that subsequent volumes can be created directly from the cache, instead of having image data transferred over the network multiple times.

The following conditions must be met in order to use ZFSSA local cache feature:

• A storage pool needs to be configured.
• REST and iSCSI services need to be turned on.
• On an OpenStack controller, cinder.conf needs to contain necessary properties used to configure and set up the ZFSSA iSCSI driver, including the following new properties:
  • zfssa_enable_local_cache: (True/False) To enable/disable the feature.
  • zfssa_cache_project: The ZFSSA project name where cache volumes are stored.

Every cache volume has two additional properties stored as ZFSSA custom schema. It is important that the schema are not altered outside of Block Storage when the driver is in use:

• image_id: stores the image id as in Image service.
• updated_at: stores the most current timestamp when the image is updated in Image service.

Supported extra specs

Extra specs provide the OpenStack storage admin the flexibility to create volumes with different characteristics from the ones specified in the cinder.conf file. The admin will specify the volume properties as keys at volume type creation. When a user requests a volume of this volume type, the volume will be created with the properties specified as extra specs.

The following extra specs scoped keys are supported by the driver:

• zfssa:volblocksize
• zfssa:sparse
• zfssa:compression
• zfssa:logbias

Volume types can be created using the cinder type-create command. Extra spec keys can be added using cinder type-key command.

Driver options

The Oracle ZFSSA iSCSI Driver supports these options: